April
2002 marks the
twenty-first
anniversary of
the CD, and in
that time the
format has
gone through
two decades of
refinement in
the forms of
oversampling,
jitter
reduction,
upsampling and
so forth. In
our continuing
understanding
of the CD
playback
process, each
innovation
resulted in
higher levels
of
sophistication,
propelling CD
playback to an
unprecedented
summit. The
most noted
member born
from a
crystallization
of all these
efforts is
possibly the
$20,000 Linn
CD-12
as reviewed by
Jim Merod.

After
careers at
prestigious
high-end audio
equipment
manufacturers
Luxman and
Kyocera, Mr.
Junji Kimura
founded 47
Laboratory in
1992. In
naming his new
company,
Kimura took
the colors of
yellow (ki-iroi)
and purple
(mura-zaki),
which contain
the syllables
of his family
name, then
coded the
colors using
resistor
color-coding
standard of 4
for yellow and
7 for purple.
Thus was born
47 Laboratory.

The
aforementioned
"Non-oversampling,
Digital-filter-less
DAC
Concept"
is authored by
Mr. Ryohei
Kusunoki, of
whose theory
Kimura is an
advocate.
Published in
the November
1996 to
December 1997
issues of the
Japanese MJ
Audio
Technology
magazine,
Kusunoki
theorizes on
an advanced
mode of CD
playback
technique
without
resorting to
oversampling
and digital
filtering:

"The
difference
between the
non-oversampling
[digital-filter-less]
DAC and the
conventional
DAC with the
digital
filter lies
whether you
attach
importance
on the
accuracy in
the time
domain or in
the
frequency
domain. In
other words,
whether you
choose the
musical
performance
or the
quality of a
sound. This
trade-off
line defines
the boundary
of the
current
digital
audio
format."

The
time and
frequency
domains
Kusunoki was
referring to
are the CD
standard's
44.1 kHz time
domain and
16-bit
frequency (or
amplitude)
domain.
Convinced of
the Redbook
CD's
engineering
validity and
potential,
Kusunoki
opined on the
digital audio
progress in
the following
excerpt:

"…in
the next
generation
digital
format
offered
today, the
selling
points for
better sound
are
quantizing
bit numbers
and sampling
frequency
rates. It
only means
lowering of
distortions
and
extension of
frequency
range. The
appearance
of CD was an
epoch-making
event as a
new format
to follow
LP. It
delivered
the sound of
the master
tape to our
listening
room. It was
a
crystallization
of efforts
of the
engineers of
that
time."

In
regard to the
digital
filter,
Kusunoki
believes it is
an unnecessary
evil. He
claims that in
both recording
and playback,
a typical
digital filter
collects data
in series,
creating a
resultant
cumulative
delay so large
that it would
become
detectable by
the human ear
ultimately.

Citing
the workings
of the
8x-oversampling
high
performance
digital filter
"SM5842"
as example,
Kusunoki
claims a
normally
insignificant
0.22-millisecond
inherent delay
in each
sampling
process will
be aggregated
into a highly
audible
2.13-millescond
total delay
time in the
SM5842's
8x-oversampling.
Claiming a
further
inevitability
of
"diffusion
of sound
coherence"
from such
serially
collected data
with the
assumption
that the
signals are
intervening
with each
other,
Kusunoki
concludes that
the less
oversampling,
the better. He
cites examples
from
prestigious
firms such as
Wadia and
Luxman with
their 13 and 3
tap
achievements
respectively -
a tap being
the waiting
interval for
signals in a
sampling
process - as
he believes
the smaller
the number of
taps would
control such
diffusion more
effectively,
providing the
inherent
advantage of
his non-oversampling
DAC.
Furthermore,
Kusunoki
considers
noise
reduction
characteristics
of digital
filters as
detrimental
given the
adversely
generated
frequency and
phase
distortions.

In
regard to
today's
sophisticated
designs in
oversampling,
Kusunoki also
reiterates
that
oversampling
is simply a
technique
enabling use
of gentler
analog filter
without
generating
additional
information.
He also states
that in
creating more
samples,
oversampling
proportionately
creates more
errors as
well.
Therefore, in
reiterating
the
theoretically
superior
accuracy of
16-bit non-oversampling
versus
8x-oversampling/20-bit,
Kusunoki
summarizes
that:

"A
natural,
stress-free
sound that
communicates
the
musicians'
intention
directly to
you…is the
sound of
non-oversampling
DAC. The
feel of this
sound is
closer to
that of
analog
reproduction."

On
signal jitter,
Kusunoki
believes that
a controlled,
strategic
distribution
of jitter will
represent a
cost-effective
and realistic
approach in
yielding an
audibly more
refined CD
sound versus
an
across-the-band
reduction
technique. In
conclusion, he
states that
the 44.1 kHz
time-domain
properties are
the
determinants
of musicality
in the D/A
conversion
process,
whereas
frequency-domain
issues, such
as jitter and
noise, are
secondary and
their roles
have been
overemphasized
by the
industry.

The
4705
Progression
"non-oversampling,
digital-filter-less"
DAC

Kusunoki's
concept is
incorporated
into the
current
statement DAC
product of
Kimura's 47
Lab, the 4705
Progression,
which features
one
surface-mounted
75-ohm digital
RCA input and
one pair of
analog RCA
outputs.
Design
highlights
are: absence
of both analog
and digital
filters, non-oversampling,
passive I/V
conversion,
claimed
shortest
signal path of
35 mm among
all DACs, and
claimed
smallest
number of
parts used in
any DAC,
namely 20
parts in
total. The
unit
automatically
adjusts to
incoming
sampling
frequencies of
32 kHz, 44 kHz
and 48 kHz and
supports
24-bit 96k Hz
signal
conversion.

Miniature
in dimensions,
the 4705
Progression is
unexpectedly
heavy at 10
lbs.
Supposedly
subduing
digital noise
dispersion,
two pieces of
solid aluminum
block anodized
in black on
the upper half
and in brushed
steel on the
bottom half
constitute the
casing of the
Progression.
47 Lab claims
significant
chassis stress
reduction with
the use of
only 3 screws,
resulting in "quick
transient
response,
totally stable
imaging and…flat
energy balance
of the
sound."
47Lab also
claims the
DAC's concave
top and bottom
serve to
"function
as spike feet
to release the
vibrations
smoothly and
stabilize
itself without
any insulators
underneath."

With
no frequency
filtering in
the
Progression,
47 Laboratory
urges user
discretion in
amplifier-speaker
matching as
energy output
equivalent to
one-third of
the music
signal at 22k
Hz will occur.
Sakura Systems
stresses the
importance of
matching
ribbon or
piezzo
speakers to
amplifiers of
recommended
power ratings.
In addition to
my observation
to follow,
refer to the
Sakura Systems
website for
more
information.

4713
Flatfish CD
Player/Transport

Interestingly
resembling the
Doctor McCoy
away-mission
portable
scanner from
the 60's Star
Trek, the
Flatfish is
the smallest
single-box CD
player I've
seen for
high-end audio
applications.
Flamboyant or
impressive-looking
it certainly
is not.
According to
the Owner's
Manual, the
Flatfish's
specific mass
and weight are
engineered to
release
disruptive
vibrations. 47
Lab believes
that damping a
chassis will
create delays
and
modulations in
the flow of
current,
therefore, by
constructing a
compact and
rigid chassis,
a quick and
proper
channeling of
mechanical
resonance,
rather than an
over-damping
of it, will
produce
sonically
superior
results.

In
strict
adherence to
this design
philosophy,
elevated by a
few
centimeters
and resting
loosely on
three tubular
stainless
steel feet in
triangular
formation, the
Flatfish is at
the mercy of
user
discreetness
in remaining
stable. To
avoid toppling
it, extra care
must be
observed in
applying force
to inserting
and pulling
cables from
the unit's
rear.

Said
to be almost
completely
free of any
construction
stress, the
150g,
0.67inch-thick
machined
aluminum board
doubles its
role as the
platform and
casing of the
Flatfish, as
well as
mounting board
for all the
driving,
pick-up
mechanisms and
circuits. 47
Lab claims
that the
unit's
lightness and
the slightly
off-centered
spindle
summarily
diffuse
vibrations,
which enables
minimal
reliance on
servo-controlled
correction
system that is
sonically
detrimental.
The company
also claims to
have achieved
quick
transient
response,
thanks to the
compactness of
the platform
and small
surface area
that limits
stored
vibration
energy to a
minimum.

With
the exception
of the remote
sensor that
faces the
listener, all
functions are
accessible
only from the
top, lending a
quaint look
befitting the
humorous Flatfish
designation.
47 Lab employs
four small
surface-mounted
toggle
switches to
control the
functions of
power on/off,
Stop/TOC,
Music Skip,
Pause/Play.
Located on the
rear are
digital
coaxial
outputs 1
& 2, and a
pair of RCA
analog
outputs. The
most unique
top-loading
design I've
seen, there is
neither a disc
chamber nor
cover. With
the spindle
being the only
breaking point
above the
surface, the
spindle base
is at the same
level of the
unit's top
plate, utterly
exposing the
laser and
pickup
mechanisms
when not
covered by
either a
mounted CD or
the included
white acrylic
lens
protector.

After
being lowered
through the
spindle, a
CD's inner
ring rests
tentatively
above the
spindle base.
A very small,
acrylic center
cap screws
down on the
spindle,
holding the
disc firmly in
place. As the
disc-loading
process is
entirely
manual, the
Flatfish won't
spin or access
the Table of
Contents until
the user flips
the TOC
toggle switch.
Afterwards,
the sky-facing
LED window
will display
total time and
number of
tracks. Again,
from the
listening
position,
track
information
becomes
guesswork as
the display is
out of sight.

The
Flatfish's
center cap is
a far cry from
the flattening
and
stabilizing
functionality
of my CEC
TL1's
substantial
full-disc
stabilizer. In
fact, as my
Salamander
Synergy 20's
top shelf on
which the
Flatfish
rested was
lower than
thigh height,
I constantly
witnessed the
alarming and
discomforting
sight of CDs
spinning in
open air.
Despite 47
Lab's claimed
minimization
of
construction
stress and
disruptive
vibrations as
advantages of
the design, it
is intriguing
that 47 Lab
would decide
on a transport
mechanism that
is not
shielded from
environmental
intrusions. It
therefore
served as
little comfort
from the fact
that the laser
assembly read
from
underneath the
disc and not
above,
exposing the
transport
innards and
the CD's label
to dust
collection.

4799
Power Dumpty
power supply

Neither
the Flatfish
nor the
Progression
could be
self-powered
and the
standalone
Power Dumpty
acted as a
shared power
supply for
both units.
Via exclusive
power line
cables, the
Power Dumpty
featured two
rear power
outputs
designed
specifically
for powering
up both
Flatfish and
Progression.
The Power
Dumpty itself
drew power via
a generic IEC
AC cord.

Epilogue

Although
"Only the
Simplest can
Accommodate
the Most
Complex"
is Mr.
Kimura's
design
philosophy,
his products
share no utter
inference with
a crude,
elementary
design. While
the
appearances of
both the
Flatfish and
Progression
are admittedly
bare, they are
the fruition
of advanced
understanding
in related
fields of
digital audio
and the laws
of physics.
His approach
to simplicity
is by far the
most
comprehensive
I've
encountered.

The
Progression is
a product of a
taxing
evolutionary
process. Its
high-performance
DAC chip, a
vital building
block in the
Progression's
performance,
is an
embodiment of
the latest in
circuit
miniaturization.
In addition,
Kimura's
unique
accomplishment
of extreme
signal path
minimization
was
undoubtedly a
distillation
of decades of
experiences
and
experimentation
from his
former
endeavors.
Therefore, the
collaboration
of Kimura and
Kusunoki,
leading up to
the noted
refinement in
theory and
practice,
deserves
admiration and
congratulation.

I
will mention
here that the
sound of the
Flatfish and
Progression
versus that of
the CEC TL1
and Wadia 27
represented
for me not
disparity, but
rather a
testimonial to
the venues
advanced and
adopted by
brilliant
designers in
the
maximization
of CD format's
potential. The
inevitable and
shocking
advancement of
CD playback
quality as
personified by
the 47 Lab
gear both
dismays and
excites me. I
wholeheartedly
consider my
five-year
ownership of
the CEC/Wadia
system an
indispensable
and rewarding
experience
because, as if
in preparation
for this
review, the
unique
perspective
the ownership
accorded me
expelled all
groundless
prejudices
toward the 47
Laboratory
Flatfish
transport and
Progression
DAC in their
laboratory-style
encapsulation.
See you next
installment
with my
subjective
evaluations.